Most of the conventional dishwashers are engaged in washing with cool water or in company with hot water introduced additionally, or with cool water and hot water alternatively by means of heating with an electric heater while almost all of them have low flow pressure. They are suitable to such occasions as a small family or for cleaning cups and other utensils which are not oily. Notwithstanding, for a hospital, hotel or restaurant, etc., where there are a large number of oily dishes, residuals and food remainings having resulted in a big problem of cleanup and disposal for the food serving industry.
Further most of the conventional dishwashers are designed with direct drain after washing up to cause a huge waste of water. Providing the wastewater is not treated it will result in a great damage to the water resource because of lowering oxygen content to evoke another environmental protection problem. It is significant that an improvement for the conventional dishwashers is necessary for ensuring a reliable way of washing clean dishes and untensils as well as the prevention of water resource waste.
In view of aforesaid defects found in the conventional dishwashers, the inventor therefore has devoted to research based on related experience to the design and manufacture of such item, and has developed the invention after persistent testings and improvements.